United Microelectronics Corp. slipped back to fourth place in 2012, as the company experienced a fall in sales in 2012.

Samsung ranked third in the list, mainly due to the demand of application processors by Apple. However, it is expected that Apple will start to move manufacturing to TSMC in 2013. Nonetheless IC Insights said it believes Samsung will challenge Globalfoundries for the number two spot in 2013.

Samsung's challenge will be to bring on replacement customers as Apple diversifies its suppliers. Samsung's executives have been in talks with ZTE and Huwaei in order to sign contracts over mobile chips.